Driving mechanism for talking film apparatus



April 7, 1936. H. KUPPENBENDER DRIVING MECHANISM FOR TALKING FILM APPARATUS Filed July 6, 1934 1.721. re 21. 171 zfl'zkjyzerzbeuizl: by:

J? i Z0131 41y.

Patented Apr. 1, 1936 PATENT OFFICE DRIVING MECHANISM FOR TALKING FILM APPARATUS Heinz Kiippenbender, Dresden, Germany, as-

signor to Zeiss Ikon Aktiengesellschai't Dresden,

Dresden, Germany Application July 6, 1934, Serial No. 734,005

In Germany July 19, 1933 1Claim. (01. 271-23) This invention relates to a driving mechanism for use in connection with talking film recording, as well as reproducing apparatuses and is in- -'tended especially for small-sized apparatuses, as 5 preferably employed by amateurs, but the invention can nevertheless be employed also in connection with the ordinary large-sized apparatuses as generally used in practice.

In order to obtain sound reproduction free 10 from disturbing oscillations from a talking film it is indispensably necessary to move the film perfectly uniformly past the place where the sound is transmitted from the film to the loudspeaker. The chief causes from which disturb- 15 ances arise are the members of the driving mechanism, such as cog-wheels, chains, or the like, as well as the sprocket rolls over which the film runs. It has already been endeavored to overcome the disturbances caused by said memgo bers by inserting into the driving mechanism fly wheel masses, elastic couplings, and the like, but the efiect has not been satisfying, as the disturbing oscillations are not entirely eliminated.

The object of the present invention is to obu u tlcally 35 and by way of example on the ompanying drawing on which Figure 1 is' a front-view of a driving mechanism improved according to this invention, and Figure 2 is aside-view. of the same. n the drawing, I (Fig. 1) denotes a. belt which 40 is driven by an electromotor (not shown) and drives in turn a shaft 2 ca rying a rotary diaphragm i8 (Fig. 2) and a small cog-wheel 3 which. meshes with a large cog-wheel ll keyed on a shaft IS on which'a sprocket roll 4 is mount- 45 ed, over which the film I9 is conducted, as shown in dotted lines and indicated by the two arrows in the upper left-hand corner of Fig. 1. On the. shaft 2 is also a-cog-wheel 5 which 50 drives a train of cog-wheels 6, I, 8 and 8, of which cog-wheels the wheel 9 is keyed on a shaft 20 on which the second sprocket-roll i0 is rigidly mounted. The film runs, of course, also over this roll, as shown, and is also led over a 55 curved pick-up member ll.

The cog-wheel 8 is keyed on a shaft II which also carries a flywheel-mass it which constitutes the member doing away with the disturbances produced by the cog-wheels. The weight of this flywheel-mass is so chosen or, in lieu thereof, said flywheel-mass is rotated with such a high 5 number of revolutions, that the disturbances produced by the train of cog-wheels are reflected back into the train itself practically as if coming from a solid wall and are absorbed therein in the form of push energy and friction energy. 10

v Furthermore, in order to render innoxious also the fine disturbing oscillations produced by defects of the sprocket roll in, a roll it has been provided which is keyed on a shaft 2| which likewise carries a flywheel-mass IS. The roll it and the flywheel-mass ii are not driven by the driving mechanism of the apparatus, but by the friction of the film running over the roll I4.

I wish it to be understood that I do not claim either of the two flywheel-masses singly, as the eilect sought to be' attained by the present invention, can-be attained solely by the simultaneous action of the two flywheel-masses, as has been ascertained by very extended experiments. The effect is practically perfect. It is now possible to run also small-sized taking and reproducing apparatuses, such as generally used by amateurs, without any internal oscillations disturbing the sounds recorded on, or reproduced, from the film. The means by which this favorable effect is attained are cheap, which is likewise important especially for amateurs.

I claim:

An arrangement particularly for small talking film apparatus for eliminating or reducing the mechanical disturbing oscillations of the record carrier for the purpose of obtaining perfect reproduction, comprising in combination a driving means, a diaphragm shaftv driven by said means, two pinions on said shaft, 9. film feeding sprocket roll carrying a gear wheel meshing with one of said pinions, a train of gears. meshing with the other of said pinions, a second film feeding sprocket roll rigidly connected with the last gear of said train, a flywheel-mass rigidly connected with one of the intermediate gears of said train and driven at a higher speed than said last mentioned sprocket roll to eliminate the fundamental disturbing frequencies produced by said train, an independent film guiding roll, and a second fiy-wheel mass rigidly connected with said guiding roll and adapted to be rotated bythe film to eliminate the higher disturbing frequencles produced by the film running over said sprocket rolls.

- nnmz KUPPENBENDER. 

